Area Code 678: Coverage, Cities, and Key Information

Area code 678 is located in Atlanta, Georgia and serves the entire Atlanta metropolitan area across 29 counties and 78 cities. Introduced in 1998, the 678 area code covers the same geographic region as Atlanta's overlay codes 404, 470, 770, and 943, operating in the Eastern Time Zone (EST/EDT). Whether you're looking for a 678 phone number, need to understand local dialing, or want to know which cities use 678, this comprehensive guide covers everything about Atlanta's 678 area code.

The Atlanta region's 11-county metropolitan area hosts approximately 5.3 million residents (2025), with an estimated GDP exceeding $570 billion, making it one of the largest economies in the United States. The region hosts 15 Fortune 500 company headquarters including Home Depot, UPS, Delta Air Lines, and Coca-Cola.

Where Is Area Code 678? Geographic Coverage and Location

Area code 678 covers metropolitan Atlanta, extending across 29 counties and serving 78 cities. This broad coverage reflects the region's interconnected nature and significant population growth that necessitated introducing 678. The five core counties within 678's coverage include:

Source: Atlanta Regional Commission 2025 Population Estimates

The complete 678 coverage area includes Barrow, Bartow, Butts, Carroll, Cherokee, Clayton, Cobb, Coweta, DeKalb, Douglas, Fayette, Forsyth, Fulton, Gwinnett, Hall, Haralson, Henry, Heard (partial), Lamar, Meriwether (partial), Newton, Oconee, Paulding, Pike, Polk, Rockdale, Spalding, and Walton counties. This widespread presence underscores its importance in the region's telecommunications network.

What Time Zone Is 678?

The 678 area code operates in the Eastern Time Zone (ET), observing Eastern Standard Time (EST, UTC-5) during winter months and Eastern Daylight Time (EDT, UTC-4) during daylight saving time from March to November.

History: How 678 Came to Be

Area code 678 launched on January 15, 1998, as an overlay to existing area codes 404 and 770. An overlay means 678 shares the same geographic footprint as these other area codes. This approach addressed increasing demand for phone numbers in the rapidly growing Atlanta metropolitan area without requiring existing users to change their numbers.

Understanding 678 vs 404 vs 770: Atlanta's Area Code History

• 1947: Area code 404 became one of the 86 original North American area codes, serving the entire state of Georgia.
• 1995: Regulators introduced area code 770 as a geographic split from 404 on August 1, 1995, serving Atlanta suburbs while 404 served downtown Atlanta.
• 1998: Area code 678 became the first overlay for the Atlanta area, covering the same territory as both 404 and 770. The overlay implementation required 10-digit dialing for all calls, meaning you must dial the area code + 7-digit number even for local calls within the same area code.
• 2001: Administrators added area code 470 on September 2, 2001, as another overlay after area code 678 approached exhaustion.
• 2022: Area code 943 commenced service on March 15, 2022, after NANPA projected a shortfall of available prefixes by mid-2023.

The overlay implementation created complexity for users and providers, requiring updates to phone systems, PBX equipment, and customer education about mandatory 10-digit dialing. However, overlays avoid the significant disruption of geographic splits, where existing customers would need to change their phone numbers. The entire metro Atlanta region with area codes 404, 770, 678, 470, and 943 functions as a single local calling area, one of the largest in the United States, with no long-distance charges between area codes.

How to Dial 678: Complete Dialing Instructions

Understanding correct dialing patterns ensures successful communication. Here's how to dial within and beyond the 678 area code:

• Local Calls (within 404, 470, 678, 770, and 943): Dial all 10 digits (area code + 7-digit number). This applies even when calling someone within the same area code. 10-digit dialing is mandatory in the Atlanta metropolitan area. Example: To call a 678 number from any Atlanta-area phone, dial 678-555-0123.

• Toll Calls (outside the local calling area): Dial 1 + 10 digits (1 + area code + 7-digit number). This applies to calls outside the Atlanta metropolitan area, even within Georgia. Example: To call Savannah (area code 912), dial 1-912-555-0123.

• Emergency Services: Dial 911 for all emergencies. This three-digit number works from any phone in the United States, including mobile phones, landlines, and VoIP services.

• International Calls: Dial 011 + country code + city code + local number. Example: To call London, UK, dial 011-44-20-xxxx-xxxx.

• Operator Assisted Calls: Dial 0 + 10 digits (0 + area code + 7-digit number). While less common today, operator assistance remains available for specific calling needs such as collect calls or operator-assisted conference calls.

These dialing patterns ensure efficient and accurate call routing, connecting you to the right person or business every time.

What Cities Use 678 Area Code? Complete City List

Area code 678 covers 78 cities across the Atlanta metropolitan area. Several key cities are particularly associated with this area code:

• Atlanta: As Georgia's capital and the region's anchor city, Atlanta hosts a population of 542,715 (2025) within city limits. The broader metropolitan statistical area exceeds 6 million residents. Atlanta hosts major corporations including Home Depot (#23 Fortune 500), UPS (#45), Delta Air Lines (#70), and Coca-Cola (#95). The city serves as a major cultural and economic center with rich history, diverse population, and a thriving arts, entertainment, and business scene.

• Alpharetta: With a population of approximately 67,213, Alpharetta has emerged as a major technology hub in the Southeast. The city hosts numerous technology companies and corporate offices, earning it the nickname "Technology City of the South." Companies with significant presence include Verizon Wireless, ADP, and various software and IT services firms.

• Marietta: Population approximately 60,867, Marietta blends historical charm and modern amenities. The city's historic Marietta Square serves as a cultural centerpiece, while the broader area supports diverse business sectors including aerospace, defense contractors, and professional services.

• Sandy Springs: A hub for both business and leisure, Sandy Springs offers corporate headquarters, upscale shopping, and residential communities. The city incorporated in 2005 and has since become one of Georgia's most affluent suburban communities with a strong commercial tax base.

• Roswell: Known for its historic sites and suburban appeal, Roswell provides a quieter alternative to the bustling city center. The city maintains a historic downtown district while supporting modern residential and business development.

• Other major cities in the 678 area include Johns Creek, Gainesville, Duluth, Dunwoody, Kennesaw, Smyrna, and Cartersville, each contributing to the region's economic diversity and residential appeal.

These cities, while distinct in character, interconnect within the 678 area code, contributing to the region's overall vibrancy and economic significance.

Telecommunications and Services: Stay Connected in 678

Area code 678 supports a wide range of telecommunication services, catering to diverse needs of residents and businesses. Choose from various options:

• Landline Services: Traditional landline services remain available within the 678 area code, offering reliable and familiar communication. Major providers include AT&T (starting at $24.99-$58/month), Ooma (starting at $19.99/month plus device cost), and VoIPLy (starting at $8.95/month). Landline pricing typically ranges from $8.95 to $72/month depending on features and calling plans.

• Mobile Services: Major carriers like AT&T, Verizon, and T-Mobile provide extensive mobile coverage in the 678 area, ensuring you stay connected on the go. Carriers can now assign mobile numbers in the Atlanta area (including 678) any of the overlay area codes (404, 470, 678, 770, or 943). All three major carriers offer 5G coverage throughout the Atlanta metropolitan area, with extensive 4G LTE backup coverage.

• VoIP Services: Voice over Internet Protocol (VoIP) services are increasingly popular, offering flexible and often cost-effective communication solutions. VoIP providers serving the 678 area include:

  • Ooma – Basic service free plus taxes, Premium $19.99/month
  • VoIPLy – Unlimited calling $8.95/month
  • RingCentral – Business plans from $20-$50/user/month
  • Nextiva – Business VoIP with advanced features starting at $25/month
  • Business-focused VoIP solutions typically cost $15-$50 per user per month and include features like call recording, video conferencing, and integrations with business software.

The availability of these diverse services ensures you can choose communication options that best suit your needs and preferences.

How to Get a 678 Phone Number

Due to high demand for phone numbers in the Atlanta metropolitan area, number availability within area code 678 can sometimes be limited. As of 2025, administrators have allocated all prefixes in area codes 404, 678, and 770, with only area codes 470 and 943 having unassigned prefixes. However, carriers always make previously used numbers available for reassignment to new customers. If you're a new resident or business seeking a 678 number, consider these strategies:

• Contact multiple service providers: Don't limit yourself to a single provider. Reaching out to several providers (AT&T, Verizon, T-Mobile for mobile; local VoIP providers for business lines) increases your chances of finding an available 678 number. Each provider maintains its own inventory of available numbers.

• Consider alternative area codes: If a 678 number isn't essential, opt for a number with one of the other overlay area codes (404, 470, 770, or 943). Since all five area codes cover the identical geographic area and are part of the same local calling zone, functionality is identical regardless of which area code you choose. Area codes 470 and 943 typically have better availability.

• Explore virtual phone number options: Virtual phone numbers can provide you with a 678 area code even if you're not physically located in the area. This offers a valuable solution for businesses establishing a local presence. Popular virtual number providers include:

  • OpenPhone – Starting at $14/user/month, includes one number
  • KrispCall – Essential plan $15/month, includes one free US number
  • Grasshopper – Plans from $14-$55/month depending on features
  • RingCentral – Business-focused, starting around $20/user/month
  • Google Voice – Free for personal use, business plans available

• Number portability: Under FCC regulations, you have the right to port (transfer) your existing phone number between carriers. If you have a 678 number and want to switch providers, you can typically keep your number. The porting process usually takes 7-10 business days for landlines and 1-2 business days for mobile numbers. Contact your new provider to initiate the port; do not cancel service with your old provider until the port completes.

• Plan ahead: If you anticipate needing a 678 number in the future, start your search early. This gives you more time to explore options and secure the number you need.

Cost considerations: New phone number costs vary significantly:

• Mobile carrier activation: Typically $0-$35 one-time activation fee, plus monthly service ($30-$80/month)
• Traditional landline: $25-$75/month depending on features
• VoIP services: $9-$50/month per line
• Virtual phone numbers: $10-$30/month per number
• Number porting: Usually free, though some providers charge $5-$15 porting fees

Follow these best practices to navigate the number acquisition process more effectively and increase your chances of obtaining a 678 number.

Learn More About Telecommunications

For more detailed information on telecommunications regulations, number availability, and related topics, explore these authoritative sources:

• Federal Communications Commission (FCC): The FCC regulates interstate and international communications by radio, television, wire, satellite, and cable. Visit their North American Numbering Plan page for detailed information on numbering policies and regulations. Contact: 1-888-CALL-FCC (225-5322).

• North American Numbering Plan Administration (NANPA): NANPA administers the North American Numbering Plan (NANP), which assigns area codes and other numbering resources. Their website offers detailed information on area code assignments, numbering plan areas, NPA exhaust projections, and related topics.

• Georgia Public Service Commission: The Georgia PSC regulates telecommunications services within the state and approves area code relief plans. They issued the official announcement for area code 943.

These resources provide a deeper understanding of the telecommunications landscape and help you stay informed about relevant regulations and changes.

678 and Atlanta's Telecommunications Future

Area code 678 plays a vital role in the Atlanta metropolitan area's dynamic telecommunications infrastructure. Whether you're a resident, business owner, or simply interested in telecommunications, understanding this area code enhances your connectivity and operations. Familiarize yourself with its geographic coverage, regulatory background, dialing patterns, cities, and available services to navigate the Atlanta telecommunications landscape more effectively.

Future Outlook

The Atlanta region continues experiencing steady population growth—adding 64,400 residents in 2024-2025 alone—which sustains demand for new phone numbers. Regulators introduced area code 943 in March 2022 after NANPA projected that available prefixes would be exhausted by mid-2023. According to NANPA's 2024 exhaust analysis, the Atlanta market has sufficient numbering resources for the near term with area codes 470 and 943 still having available capacity.

However, the proliferation of mobile devices, IoT (Internet of Things) devices, and business lines continues driving demand. Industry projections suggest the Atlanta market may require additional area code relief within 5-10 years, though VoIP technology and more efficient number allocation may extend this timeline.

Technology Impact

New communications technologies are reshaping area code demand and usage:

• VoIP and cloud communications: Businesses increasingly adopt VoIP systems that don't require traditional phone line infrastructure, though they still need phone numbers for caller identification.
• Mobile-first communications: Younger demographics prefer messaging apps and mobile communication over traditional voice calls, potentially slowing the rate of number exhaustion.
• Number pooling: Improved number allocation efficiency allows carriers to share blocks of numbers rather than requiring entire 10,000-number prefixes, extending the life of existing area codes.

As the Atlanta area continues growing and evolving, area code 678 will remain a key component of its communication network, connecting people and businesses across the region. The introduction of 678 in 1998 marked a significant turning point in Atlanta's growth, reflecting the increasing complexity and interconnectedness of what has become one of America's most dynamic metropolitan regions.